Even at this first glance in the wavering light of the lantern Hillyard realised that a change had come in the aspect of his friend.  It was not a look of age, but authority clothed him as with a garment.  Rayne and Hillyard passed into the chamber.  Luttrell turned his head and welcomed Hillyard with a smile.  But he did not move and immediately afterwards he raised his face to the roof.

“Are you ready up there?”

An English voice replied through the planks.

“Yes, sir,” and immediately afterwards a dull and heavy weight like a full sack was dumped upon the platform above their heads.

“Good!”

Luttrell turned towards the giant.

“Are you ready?  And you know the signal?”

The Sudanese soldier grinned in delighted anticipation, with a flash of big white teeth, and took a firmer grip of his mallet and swung it over his shoulder.

“Good.  Now pay attention,” said Luttrell, “so that all may be well and seemly done.”

The Sudanese fixed his eyes upon Luttrell’s foot and Luttrell began to talk, rapidly and rather to himself than to his audience.  Hillyard could make neither head nor tail of the strange scene.  It was evident that Luttrell was rehearsing a speech, but why?  And what had the Sudanese with the mallet to do with it?

A sudden and rapid sequence of events brought the truth home to him with a shock.  At a point of his speech Luttrell stamped twice, and the Sudanese soldier swung his mallet with all his force.  The head of it struck the great support full and square.  The beam jumped from its position, hopped once on its end, and fell with a crash.  And from above there mingled with the crash a most horrid clang, for, with the removal of the beam, two trap-doors swung downwards.  Hillyard looked up; he saw the stars, and something falling.  Instinctively he stepped back and shut his eyes.  When he looked again, within the chamber, midway between the floor and roof, two sacks dangling at the end of two ropes spun and jerked—­as though they lived.

Rayne had stepped back and stood quivering from head to foot by Hillyard’s side; Hillyard himself felt sick.  He knew very well now what he was witnessing—­the rehearsal of an execution.  The Sudanese soldiers were grinning from ear to ear with delight and pride.  The one person quite unmoved was Harry Luttrell, whose ingenuity had invented the device.

“Let it be done just so,” he said to the soldiers.  “I shall not forgive a mistake.”

They saluted, and he dismissed them and turned at last to Martin Hillyard.

“It’s good to see you again,” he said, as he shook hands; and then he looked sharply into Hillyard’s face and laughed.  “Shook you up a bit, that performance, eh?  Well, they bungled things in Khartum a little while ago.  I can’t afford awkwardness here.”

Senga was in the centre of that old Khalifa’s tribe which not so many years ago ruled in Omdurman.  It was always restless, always on the look-out for a Messiah.